Squash hybrid sv0474yg and parents thereof

ABSTRACT

The invention provides seed and plants of squash hybrid SV0474YG and the parent lines thereof. The invention thus relates to the plants, seeds and tissue cultures of squash hybrid SV0474YG and the parent lines thereof, and to methods for producing a squash plant produced by crossing such plants with themselves or with another squash plant, such as a plant of another genotype. The invention further relates to seeds and plants produced by such crossing. The invention further relates to parts of such plants, including the fruit and gametes of such plants.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of U.S. Provisional Appl. Ser. No. 62/004,797, filed May 29, 2014, the entire disclosure of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to the field of plant breeding and, more specifically, to the development of squash hybrid SV0474YG and the inbred squash lines ZGY-EH09012 and ZGN-EH10951T.

BACKGROUND OF THE INVENTION

The goal of vegetable breeding is to combine various desirable traits in a single variety/hybrid. Such desirable traits may include any trait deemed beneficial by a grower and/or consumer, including greater yield, resistance to insects or disease, tolerance to environmental stress, and nutritional value.

Breeding techniques take advantage of a plant's method of pollination. There are two general methods of pollination: a plant self-pollinates if pollen from one flower is transferred to the same or another flower of the same plant or plant variety. A plant cross-pollinates if pollen comes to it from a flower of a different plant variety.

Plants that have been self-pollinated and selected for type over many generations become homozygous at almost all gene loci and produce a uniform population of true breeding progeny, a homozygous plant. A cross between two such homozygous plants of different genotypes produces a uniform population of hybrid plants that are heterozygous for many gene loci. Conversely, a cross of two plants each heterozygous at a number of loci produces a population of hybrid plants that differ genetically and are not uniform. The resulting non-uniformity makes performance unpredictable.

The development of uniform varieties requires the development of homozygous inbred plants, the crossing of these inbred plants, and the evaluation of the crosses. Pedigree breeding and recurrent selection are examples of breeding methods that have been used to develop inbred plants from breeding populations. Those breeding methods combine the genetic backgrounds from two or more plants or various other broad-based sources into breeding pools from which new lines and hybrids derived therefrom are developed by selfing and selection of desired phenotypes. The new lines and hybrids are evaluated to determine which of those have commercial potential.

SUMMARY OF THE INVENTION

In one aspect, the present invention provides a squash plant of the hybrid designated SV0474YG, the squash line ZGY-EH09012 or squash ZGN-EH10951T. Also provided are squash plants having all the physiological and morphological characteristics of such a plant. Parts of these squash plants are also provided, for example, including pollen, an ovule, scion, a rootstock, a fruit, and a cell of the plant.

In another aspect of the invention, a plant of squash hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T comprising an added heritable trait is provided. The heritable trait may comprise a genetic locus that is, for example, a dominant or recessive allele. In one embodiment of the invention, a plant of squash hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T is defined as comprising a single locus conversion. In specific embodiments of the invention, an added genetic locus confers one or more traits such as, for example, herbicide tolerance, insect resistance, disease resistance, and modified carbohydrate metabolism. In further embodiments, the trait may be conferred by a naturally occurring gene introduced into the genome of a line by backcrossing, a natural or induced mutation, or a transgene introduced through genetic transformation techniques into the plant or a progenitor of any previous generation thereof. When introduced through transformation, a genetic locus may comprise one or more genes integrated at a single chromosomal location.

The invention also concerns the seed of squash hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T. The squash seed of the invention may be provided as an essentially homogeneous population of squash seed of squash hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T. Essentially homogeneous populations of seed are generally free from substantial numbers of other seed. Therefore, seed of hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T may be defined as forming at least about 97% of the total seed, including at least about 98%, 99% or more of the seed. The seed population may be separately grown to provide an essentially homogeneous population of squash plants designated SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T.

In yet another aspect of the invention, a tissue culture of regenerable cells of a squash plant of hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T is provided. The tissue culture will preferably be capable of regenerating squash plants capable of expressing all of the physiological and morphological characteristics of the starting plant, and of regenerating plants having substantially the same genotype as the starting plant. Examples of some of the physiological and morphological characteristics of the hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T include those traits set forth in the tables herein. The regenerable cells in such tissue cultures may be derived, for example, from embryos, meristems, cotyledons, pollen, leaves, anthers, roots, root tips, pistils, flowers, seed and stalks. Still further, the present invention provides squash plants regenerated from a tissue culture of the invention, the plants having all the physiological and morphological characteristics of hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T.

In still yet another aspect of the invention, processes are provided for producing squash seeds, plants and fruit, which processes generally comprise crossing a first parent squash plant with a second parent squash plant, wherein at least one of the first or second parent squash plants is a plant of squash line ZGY-EH09012 or squash ZGN-EH10951T. These processes may be further exemplified as processes for preparing hybrid squash seed or plants, wherein a first squash plant is crossed with a second squash plant of a different, distinct genotype to provide a hybrid that has, as one of its parents, a plant of squash line ZGY-EH09012 or squash ZGN-EH10951T. In these processes, crossing will result in the production of seed. The seed production occurs regardless of whether the seed is collected or not.

In one embodiment of the invention, the first step in “crossing” comprises planting seeds of a first and second parent squash plant, often in proximity so that pollination will occur for example, mediated by insect vectors. Alternatively, pollen can be transferred manually. Where the plant is self-pollinated, pollination may occur without the need for direct human intervention other than plant cultivation.

A second step may comprise cultivating or growing the seeds of first and second parent squash plants into plants that bear flowers. A third step may comprise preventing self-pollination of the plants, such as by emasculating the flowers (i.e., killing or removing the pollen).

A fourth step for a hybrid cross may comprise cross-pollination between the first and second parent squash plants. Yet another step comprises harvesting the seeds from at least one of the parent squash plants. The harvested seed can be grown to produce a squash plant or hybrid squash plant.

The present invention also provides the squash seeds and plants produced by a process that comprises crossing a first parent squash plant with a second parent squash plant, wherein at least one of the first or second parent squash plants is a plant of squash hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T. In one embodiment of the invention, squash seed and plants produced by the process are first generation (F₁) hybrid squash seed and plants produced by crossing a plant in accordance with the invention with another, distinct plant. The present invention further contemplates plant parts of such an F₁ hybrid squash plant, and methods of use thereof. Therefore, certain exemplary embodiments of the invention provide an F₁ hybrid squash plant and seed thereof.

In still yet another aspect, the present invention provides a method of producing a plant derived from hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T, the method comprising the steps of: (a) preparing a progeny plant derived from hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T, wherein said preparing comprises crossing a plant of the hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T with a second plant; and (b) crossing the progeny plant with itself or a second plant to produce a seed of a progeny plant of a subsequent generation. In further embodiments, the method may additionally comprise: (c) growing a progeny plant of a subsequent generation from said seed of a progeny plant of a subsequent generation and crossing the progeny plant of a subsequent generation with itself or a second plant; and repeating the steps for an additional 3-10 generations to produce a plant derived from hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T. The plant derived from hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T may be an inbred line, and the aforementioned repeated crossing steps may be defined as comprising sufficient inbreeding to produce the inbred line. In the method, it may be desirable to select particular plants resulting from step (c) for continued crossing according to steps (b) and (c). By selecting plants having one or more desirable traits, a plant derived from hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T is obtained which possesses some of the desirable traits of the line/hybrid as well as potentially other selected traits.

In certain embodiments, the present invention provides a method of producing food or feed comprising: (a) obtaining a plant of squash hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T, wherein the plant has been cultivated to maturity, and (b) collecting at least one squash from the plant.

In still yet another aspect of the invention, the genetic complement of squash hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T is provided. The phrase “genetic complement” is used to refer to the aggregate of nucleotide sequences, the expression of which sequences defines the phenotype of, in the present case, a squash plant, or a cell or tissue of that plant. A genetic complement thus represents the genetic makeup of a cell, tissue or plant, and a hybrid genetic complement represents the genetic make up of a hybrid cell, tissue or plant. The invention thus provides squash plant cells that have a genetic complement in accordance with the squash plant cells disclosed herein, and seeds and plants containing such cells.

Plant genetic complements may be assessed by genetic marker profiles, and by the expression of phenotypic traits that are characteristic of the expression of the genetic complement, e.g., isozyme typing profiles. It is understood that hybrid SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T could be identified by any of the many well known techniques such as, for example, Simple Sequence Length Polymorphisms (SSLPs) (Williams et al., Nucleic Acids Res., 1 8:6531-6535, 1990), Randomly Amplified Polymorphic DNAs (RAPDs), DNA Amplification Fingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs), Arbitrary Primed Polymerase Chain Reaction (AP-PCR), Amplified Fragment Length Polymorphisms (AFLPs) (EP 534 858, specifically incorporated herein by reference in its entirety), and Single Nucleotide Polymorphisms (SNPs) (Wang et al., Science, 280:1077-1082, 1998).

In still yet another aspect, the present invention provides hybrid genetic complements, as represented by squash plant cells, tissues, plants, and seeds, formed by the combination of a haploid genetic complement of a squash plant of the invention with a haploid genetic complement of a second squash plant, preferably, another, distinct squash plant. In another aspect, the present invention provides a squash plant regenerated from a tissue culture that comprises a hybrid genetic complement of this invention.

Any embodiment discussed herein with respect to one aspect of the invention applies to other aspects of the invention as well, unless specifically noted.

The term “about” is used to indicate that a value includes the standard deviation of the mean for the device or method being employed to determine the value. The use of the term “or” in the claims is used to mean “and/or” unless explicitly indicated to refer to alternatives only or the alternatives are mutually exclusive. When used in conjunction with the word “comprising” or other open language in the claims, the words “a” and “an” denote “one or more,” unless specifically noted otherwise. The terms “comprise,” “have” and “include” are open-ended linking verbs. Any forms or tenses of one or more of these verbs, such as “comprises,” “comprising,” “has,” “having,” “includes” and “including,” are also open-ended. For example, any method that “comprises,” “has” or “includes” one or more steps is not limited to possessing only those one or more steps and also covers other unlisted steps. Similarly, any plant that “comprises,” “has” or “includes” one or more traits is not limited to possessing only those one or more traits and covers other unlisted traits.

Other objects, features and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and any specific examples provided, while indicating specific embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides methods and compositions relating to plants, seeds and derivatives of squash hybrid SV0474YG, squash line ZGY-EH09012 and squash ZGN-EH10951T.

Squash hybrid SV0474YG is a medium-green colored zucchini hybrid with exceptionally high productivity, highly uniform cylindrical fruits, and resistance to several important viral pathogens.

A. Origin and Breeding History of Squash Hybrid Sv0474Yg

The parents of hybrid SV0474YG are ZGY-EH09012 and ZGN-EH10951T. These parents were created as follows:

Hybrid SV0474YG was first produced in Year 26 as a cross between a line closely related to ZGY-EH09012 and a line closely related to ZGN-EH10951T. The hybrid showed good performance (high yield, high quality, and high fruit uniformity) in open field trials in Year 26.

Parent ZGY-EH09012 was developed by an initial cross between an F6 generation proprietary breeding line (ZGY-EH09012 female parent) and a BC4F9 generation proprietary breeding line (ZGY-EH09012 male parent). This cross was made in Year 19, and while the hybrid was not commercially acceptable, it was recognized as a useful source of new germplasm for breeding, because it recombined the disease resistance of the female parent line (ZYMV, WMV, PRSV, SLCV, CuLCV) with the fruit shape and disease resistance of the male parent (more cylindrical, elongated shape and resistance for ZYMV and PM). The F1 generation was self pollinated without selection, but the F2 generation was self pollinated following inoculation with a cocktail of viruses (ZYMV, WMV, PRSV) and selection of survivors that were asymptomatic. The F3 generation inoculated with SLCV, and asymptomatic plants were selected and self pollinated. The F4 generation seedlings were inoculated with a cocktail of viruses (ZYMV, WMV, PRSV), and survivors were self-pollinated. The F5 and F6 generations were self pollinated without selection, and harvested as individual plants. The F7 generation was also pollinated without phenotypic selection, and an individual plant was chosen and designated as ZGY-EH09012. All subsequent inbred generations of ZGY-EH09012 derive from this individual F7 generation plant.

The proprietary female parent of ZGY-EH09012 was developed from a breeding strategy to recombine the key horticultural and disease resistance traits of several starting germplasm components. The common public source germplasm components (accessions) of that female parent were three distinct selections from the traditional open pollinated landrace of squash common in Mexico and North Africa known as Grey Zucchini in Mexico and Small Green Algerian in North Africa, and a selection from the traditional open pollinated “Caserta” landrace from central Italy. In addition, the initial sources of the key traits of value (resistance to Zucchini Yellow Mosaic Virus (ZYMV), Watermelon Mosaic Virus II (WMV-II), and Squash leaf curl virus (SLCV)) were a diverse early generation population of squash distributed by Henry Munger of Cornell University in Year 1 to collaborating seed companies (85-187-5X184) and a breeding selection developed by Sergio Garza from the Universidad de Sonora in Year 13 originally designated as A98S85 The proprietary female parent of ZGY-EH09012 was developed through multiple generations of inbreeding (controlled self-pollination) and crossing. Between Year 1-13 two individual selections from the 85-187-5X184 breeding line were used to develop parent lines with resistance to ZYMV, WMV, and PRSV. One selection was crossed to a selection from grey zucchini, and the other was crossed to a selection from Caserta. In both cases, segregating generations were selected under conditions of strong viral disease pressure, and in both cases a BC1F4 generation parent line was developed. The lineage originally crossed to the grey zucchini selection was advanced to the F8 generation, and designated as ZGY-47-5014. Meanwhile, the A98S85 parent was crossed to a second selection from the grey zucchini landrace, and 4 generations of self pollination were performed before a backcross was bade to the same (second) grey zucchini landrace. The backcross was then selfed for 3 generations before it was observed (in field trials) to be resistant to SLCV. The BC1F4 generation of that grey zucchini type line (enhanced with resistance to SLCV) was then crossed to ZGY-47-5014 in early Year 16. The F1 from that cross was then backcrossed in late Year 16 to ZGY-47-5014. Multiple BC1F1 generation individuals were then crossed to the BC1F4 generation parent line that was developed from 85-187-5X184 and the Caserta type selection in early Year 17. The resulting diverse F1 population was inoculated with a cocktail including ZYMV, WMV, and PRSV in Year 17, and individual resistant plants were selected and self pollinated. The F2 generation was sown in a location with a history of heavy SLCV infection, and the best progeny were selected and self pollinated. The F3 generation was mechanically inoculated with SLCV, and surviving progeny were selected and self pollinated. Individual plants from the F4 through F6 generations were self pollinated without selection. An F6 generation individual was selected as the female parent for the hybrid that later led to the development of ZGY-EH09012.

The male parent leading to the development of ZGY-EH09012 was developed using two components, a selection from the Caserta landrace and a genotype distributed by the French national agricultural research agency INRA, known as C88. The male parent was developed by crossing the two parent lines, self pollination of the hybrid, then two generations of self pollination following selection under heavy pressure of ZYMV and PM (only resistant individuals selected). After reaching the F4 generation, a selection from the breeding line was backcrossed again to the selection from the Caserta landrace. This pattern was repeated 5 times, to create the BC4F4 generation of these two initial parents. The BC4F4 generation selection was then self pollinated without selection until the BC4F9 generation, where it was used in the cross eventually leading to ZGY-EH09012.

ZGN-EH10951T was developed by an initial cross between the proprietary inbred line ZGN-130-1041T (patent publication number U.S. Pat. No. 8,119,863 B2, U.S. application Ser. No. 12/197,820, also published as US2009-0064366) and a proprietary F6 breeding line later (F9 generation) known as ZGN-130-1096 (patent publication number US2013-0312135 A1, U.S. application Ser. No. 13/658,788). The finished version of this hybrid later became known as ZGNEHH6009, and is an established commercial variety. The unfinished version of this hybrid (inbred X F6) was used as a source of new breeding germplasm. The F1 generation was self pollinated without phenotypic selection. The F2 generation was inoculated with a cocktail that included CMV, ZYMV, and PRSV, and asymptomatic survivors were selected and self pollinated. In the F3 generation seedlings were inoculated with a cocktail that included ZYMV and CMV, and asymptomatic survivors were selected and self pollinated. In the F4 generation selection was based solely on phenotypic traits (growth habit, fruit shape and color). The F5 and F6 generations were advanced without selection, and an individual F7 plant was selected and designated as ZGN-EH10951T. All subsequent increases of ZGN-EH10951T derive from that individual F7 generation plant.

The parent lines are uniform and stable, as is a hybrid produced therefrom. A small percentage of variants can occur within commercially acceptable limits for almost any characteristic during the course of repeated multiplication. However no variants are expected.

B. Physiological and Morphological Characteristics of Squash Hybrid SV0474YG, Squash Line ZGY-EH09012 and Squash ZGN-EH10951T

In accordance with one aspect of the present invention, there is provided a plant having the physiological and morphological characteristics of squash hybrid SV0474YG and the parent lines thereof. A description of the physiological and morphological characteristics of such plants is presented in Tables 1-3.

TABLE 1 Physiological and Morphological Characteristics of Hybrid SV0474YG Comparison Variety CHARACTERISTIC SV0474YG Fordhook (*HP 111) 1. Species Pepo Pepo 2. Kind/Use squash pumpkin 3. Type summer (vegetable marrow) summer 4. Cotyledon length 44.3 mm 46.0 mm width 31.1 mm 30.0 mm apex rounded rounded veining plainly visible plainly visible color medium green medium green color (RHS Color Chart) 143A 143A 5. Seedling shape of cotyledons broad elliptic circular (Cinderella, Goldi) intensity of green color of medium (Cora) medium cotyledons cross section of straight (Sunburst) concave cotyledons 6. Mature Plant growth habit bush bush plant type prickly pilose 7. Main Stem cross-section shape round round diameter at mid-point of 22.9 mm 31.2 mm 1^(st) internode average length 21.1 cm 34.6 cm average number of  19.4  26.6 internodes 8. Stem color completely green (Becky) completely green intensity of green color dark (Greyzini) dark mottling absent (Cinderella) absent tendrils absent to rudimentary absent to rudimentary (Goldrush, Sylvania) (Goldrush, Sylvania) 9. Plant growth habit bush (Greyzini) bush branching absent (Goldi) absent 10. Leaves blade shape reniform reniform blade form deep lobed deep lobed margin dentate dentate margin edges frilled frilled average width 34.6 cm 25.9 cm average length 30.4 cm 22.3 cm leaf surface smooth blistered dorsal surface pubescence soft hairy bristled vental surface pubescence soft hairy bristled color dark green dark green color (RHS Color Chart) 137A 137A leaf blotching blotched with gray blotched with gray leaf blade: size medium (Ambassador) medium leaf blade: incisions deep (Civac) deep leaf blade: intensity of medium (Cora) light green color of upper surface leaf blade: silvery patches present (Civac) present leaf blade: relative area small (Aziz) very small covered by silvery patches average petiole length 34.2 cm 33.3 cm petiole length medium (Goldi) long petiole: number of many (White Bush Scallop) few prickles 11. Flower pistillate flower: average 10.8 cm 11.5 cm diameter pistillate flower: ovary drum-like drum-like pistillate flower: average 1.6 cm 2.0 cm pedicel length pistillate flower: margin curved curved shape pistillate flower: margin frilled frilled edges pistillate flower: average 1.0 mm 0.9 mm sepal width pistillate flower: average 3.9 mm 3.4 mm sepal length pistillate flower: color orange orange pistillate flower: color 17A 23A (RHS Color Chart) staminate flower: average 14.3 mm 15.2 mm sepal length staminate flower: average 2.2 mm 2.1 mm sepal width staminate flower: average 114.8 mm 126.6 mm pedicel length staminate flower: color orange orange staminate flower: color 17A 23A (RHS Color Chart) female flower: ring at present (Aurore) present inner side of corolla female flower: color of green (Aurore, Early White green ring at inner side of Bush Scallop, President) corolla female flower: intensity of weak (Maya, Sardane) strong green color of ring at inner side of corolla (varieties with green ring at inner side of corolla) male flower: ring at inner present (Goldi) present side of corolla male flower: color of ring green (Austral, Belor, Goldi) green at inner side of corolla male flower: intensity of strong (Goldi) medium green color of ring at inner side of corolla 12. Fruit market maturity: average 15.5 cm 14.9 cm length market maturity: average 2.7 cm 2.6 cm width - stem end at market maturity: 0.9 cm 1.0 cm average width - blossom end market maturity: average 145.6 gm 134.1 gm weight market maturity: shape banana banana according to variety type market maturity: apex rounded rounded market maturity: base rounded rounded market maturity: ribs none inconspicuous market maturity: fruit smooth smooth surface market maturity: warts none none market maturity: blossom raised acorn raised acorn scar button young fruit: ratio length/ large (Carlotta) small maximum diameter (zucchini type varieties) young fruit: general shape cylindrical (Ambassador, cylindrical (zucchini and rounded Ibis) zucchini type varieties) young fruit: main color of green (Elite, Opal, Romano) green skin (excluding color of ribs or grooves) young fruit: intensity of dark dark green color of skin (only (Arlesa, Sandra, Zefira) varieties with green color of skin) general shape cylindrical cylindrical length (zucchini type long (Carlotta) long varieties) maximum diameter small (Goldi) medium (zucchini type varieties) ratio length/maximum large (Carlotta) medium diameter (zucchini type varieties) blossom end (zucchini and rounded pointed neck type varieties) grooves absent absent ribs absent absent main color of skin green (Ambassador, Baby green (excluding color of dots, Bear) patches, stripes and bands) intensity of green color of dark (Cora) very dark skin (only varieties with green color of skin) stripes in grooves absent (Baby Bear, Jack Be absent Little) dots absent (Sunburst) absent secondary green color absent (Grey Zucchini, absent between ribs (excluding Small Sugar) dots) warts on skin absent absent size of flower scar small (Goldi) small length of peduncle medium (Cinderella) medium color of peduncle green (Ambassador) green intensity of green color of dark (Gold Rush) dark peduncle mottling of peduncle present (Elite) present ripe fruit: main color of dark green dark green skin (excluding color of mottles, patches, stripes and bands) secondary color of skin orange orange green hue absent (Jedida) absent ripe fruit: color of flesh yellow yellow (Sunburst, Vegetable Spaghetti) ripe fruit: lignified rind present (Elite, Little Gem, present Scallopini, Yellow Summer Crookneck) ripe fruit: structure of fibrous (Vegetable fibrous flesh Spaghetti) 13. Rind average thickness at 3.2 mm 2.1 mm medial toughness hard hard overall color pattern irregular irregular main or ground color grayish-green grayish green main or ground color N189A N189A (RHS Color Chart) color of blotches grayish-orange grayish-orange RHS Color Chart for N163A N163D spots color 14. Flesh average blossom end 35.1 mm 29.7 mm thickness average medial thickness 36.1 mm 36.8 mm average stem end 33.8 mm 36.6 mm thickness texture (fine, granular, granula fine lumpy or stringy) texture (soft, firm or firm firm brittle) texture (dry, moist or moist moist juicy) flavor sweet sweet quality excellent excellent color creamy-orange yellow color (RHS Color Chart) 157B 4D 15. Seed Cavity average length 30.2 cm 38.0 cm average width 5.9 cm 8.9 cm location conforms to fruit shape conforms to fruit shape placental tissue abundant moderately abundant center core inconspicuous inconspicuous 16. Fruit Stalks average length 2.5 cm 3.1 cm average diameter 2.6 cm 2.0 cm cross-section shape round irregular twisting twisted not twisted tapering not tapered not tapered straightness curved straight texture spongy hard furrows deep deep surface spiny rough attachment end expanded slightly expanded detaches with difficulty easily color medium green dark green color (RHS Color Chart) 143A 147A 17. Seeds average length 13.0 mm 13.8 mm average width 7.6 mm 8.9 mm average thickness 2.9 mm 3.0 mm face surface smooth smooth color cream cream color (RHS Color Chart) 155C 155C luster dull glossy margin straight straight margin edge rounded rounded separation from pulp easy moderately easy average grams per 100 13.0 gm 16.0 gm seeds average number of seeds 330.8 143.8 per fruit seed coat normal normal size medium (Diamant) medium shape elliptic (Elite) elliptic hull present (Baby Bear, Elite) present appearance of hull fully developed (Elite) fully developed color of hull cream (De Nice à Fruit cream Rond) fruit type: zucchini fruit: patches, stripes or present (Elite, Greyzini) bands in ripe stage (if zucchini type) *These are typical values. Values may vary due to environment. Other values that are substantially equivalent are also within the scope of the invention.

TABLE 2 Physiological and Morphological Characteristics of Line ZGY-EH09012 Comparison Variety FORDHOOK (ZGN CHARACTERISTIC ZGY-EH09012 47-111*HP 111) 1. Species Pepo Pepo 2. Kind/Use squash squash 3. Type summer (vegetable marrow) summer 4. Cotyledon length 37.3 mm 39.4 mm width 24.7 mm 28.2 mm apex tapered rounded veining plainly visible prominent color medium green medium green color (RHS Color Chart) 143A 143A 5. Seedling shape of cotyledons narrow elliptic (Bianchini) elliptic intensity of green color of medium (Cora) medium cotyledons cross section of concave concave cotyledons 6. Mature Plant growth habit bush bush plant type prickly prickly 7. Main Stem cross-section shape angled round diameter at mid-point of 28.3 mm 32.1 mm 1^(st) internode average length 39.9 cm 39.6 cm average number of  26.3  28.8 internodes 8. Stem color completely green (Becky) completely green intensity of green color dark dark (Greyzini) mottling absent (Cinderella) absent tendrils well developed (Baby Bear, well developed Greyzini) 9. Plant growth habit bush (Greyzini) bush branching absent (Goldi) absent bush varieties only: erect (Blanche non coureuse erect to semi-erect attitude of petiole 3, Yellow Crookneck) (excluding lower external leaves) 10. Leaves blade shape reniform reniform blade form deep lobed deep lobed margin denticulate denticulate margin edges frilled frilled average width 35.7 cm 36.3 cm average length 31.2 cm 28.7 cm leaf surface blistered blistered dorsal surface pubescence bristled soft hairy vental surface pubescence soft hairy soft hairy color dark green dark green color (RHS Color Chart) 136A 139A leaf blotching blotched with gray blotched with gray leaf blade: size medium medium (Ambassador) leaf blade: incisions deep (Civac) medium leaf blade: intensity of dark (Everest) dark green color of upper surface leaf blade: silvery patches present (Civac) present leaf blade: relative area medium (Ambassador) medium covered by silvery patches average petiole length 32.1 cm 36.9 cm petiole length medium (Goldi) long petiole: number of many (White Bush Scallop) absent or very few prickles 11. Flower pistillate flower: average 13.8 cm 13.3 cm diameter pistillate flower: ovary drum-like drum-like pistillate flower: average 1.2 cm 2.2 cm pedicel length pistillate flower: margin curved curved shape pistillate flower: margin frilled frilled edges pistillate flower: average 1.3 mm 1.2 mm sepal width pistillate flower: average 3.9 mm 3.6 mm sepal length pistillate flower: color orange orange pistillate flower: color 25B 23A (RHS Color Chart) staminate flower: average 11.6 mm 13.2 mm sepal length staminate flower: average 2.0 mm 2.0 mm sepal width staminate flower: average 62.3 mm 47.9 mm pedicel length staminate flower: color orange orange RHS Color Chart values 24A 24A female flower: ring at absent present inner side of corolla (Cinderella, Greyzini) male flower: ring at inner present (Goldi) present side of corolla male flower: color of ring green (Austral, Belor, Goldi) green at inner side of corolla male flower: intensity of medium (Verdi) strong green color of ring at inner side of corolla 12. Fruit market maturity: average 15.1 cm 16.5 cm length market maturity: average 2.1 cm 2.9 cm width - stem end at market maturity: 1.0 cm 1.2 cm average width - blossom end market maturity: average 186.9 gm 166.4 gm weight market maturity: shape banana banana according to variety type market maturity: apex rounded rounded market maturity: base rounded rounded market maturity: ribs inconspicuous inconspicuous market maturity: rib shallow shallow furrow depth market maturity: rib medium wide medium wide furrow width market maturity: fruit smooth smooth surface market maturity: warts none none market maturity: blossom raised acorn slightly extended scar button young fruit: ratio length/ small (Opal) medium maximum diameter (zucchini type varieties) young fruit: general shape tapered elliptical (Top Kapi) cylindrical (zucchini and rounded zucchini type varieties) young fruit: main color of green (Elite, Opal, Romano) green skin (excluding color of ribs or grooves) young fruit: intensity of light (Arlika) dark green color of skin (only varieties with green color of skin) general shape club shaped cylindrical length (zucchini type medium (Cora) medium varieties) maximum diameter small (Goldi) small (zucchini type varieties) ratio length/maximum medium (Cora) medium diameter (zucchini type varieties) blossom end (zucchini and rounded rounded neck type varieties) grooves absent present ribs present absent protrusion of ribs very weak (Ledo, Tivoli) main color of skin green (Ambassador, Baby green (excluding color of dots, Bear) patches, stripes and bands) intensity of green color of light very dark skin (only varieties with green color of skin) stripes in grooves absent (Baby Bear, Jack Be absent Little) dots present (Gold Rush, Table absent Queen) size of main dots very small (Badger Cross) secondary green color absent (Grey Zucchini, between ribs (excluding Small Sugar) dots) warts on skin absent absent size of flower scar small (Goldi) medium length of peduncle short (Clarita) long color of peduncle green (Ambassador) green intensity of green color of dark (Gold Rush) dark peduncle mottling of peduncle present (Elite) present ripe fruit: main color of orange (Autumn Gold) green skin (excluding color of mottles, patches, stripes and bands) ripe fruit: intensity of dark main color of skin (only yellow and orange) ripe fruit: color of flesh yellow yellow (Sunburst, Vegetable Spaghetti) ripe fruit: lignified rind present (Elite, Little Gem, present Scallopini, Yellow Summer Crookneck) ripe fruit: structure of fibrous (Vegetable fibrous flesh Spaghetti) 13. Rind average thickness at 2.4 mm 2.1 mm medial toughness hard hard overall color pattern regular irregular main or ground color yellowish-orange grayish-green main or ground color 24A N189A (RHS Color Chart) color of spots Creamy-orange RHS Color Chart for 23C spots color 14. Flesh average blossom end 37.4 mm 29.6 mm thickness average medial thickness 43.8 mm 38.0 mm average stem end 34.3 mm 37.7 mm thickness texture (fine, granular, fine fine lumpy or stringy) texture (soft, firm or firm firm brittle) texture (dry, moist or moist moist juicy) flavor slightly sweet slightly sweet quality good good color greenish-white greenish-white color (RHS Color Chart) 149D A54D 15. Seed Cavity average length 26.0 cm 34.2 cm average width 5.9 cm 6.5 cm location conforms to fruit shape conforms to fruit shape placental tissue abundant moderately abundant center core prominent inconspicious 16. Fruit Stalks average length 2.2 cm 3.2 cm average diameter 1.8 cm 2.0 cm cross-section shape irregular irregular twisting not twisted not twisted tapering tapered tapered straightness slightly curved slightly curved texture hard hard furrows deep deep surface rough smooth attachment end expanded expanded detaches with difficulty with difficulty color dark green dark green color (RHS Color Chart) 147A 137B 17. Seeds average length 14.3 mm 13.6 mm average width 8.7 mm 8.5 mm average thickness 2.5 mm 3.4 mm face surface smooth smooth color cream cream color (RHS Color Chart) 155A 155A luster glossy glossy margin curved curved margin edge rounded rounded separation from pulp easy easy average grams per 100 11.4 gm 15.4 gm seeds average number of seeds 185.1 117.4 per fruit seed coat normal normal size medium (Diamant) medium shape elliptic (Elite) elliptic hull present (Baby Bear, Elite) present appearance of hull fully developed (Elite) fully developed color of hull cream (De Nice à Fruit cream Rond) fruit type: zucchini fruit: patches, stripes or absent (Ambassador, Black bands in ripe stage (if Jack) zucchini type) *These are typical values. Values may vary due to environment. Other values that are substantially equivalent are also within the scope of the invention.

TABLE 3 Physiological and Morphological Characteristics of ZGN-EH10951T Comparison Variety CHARACTERISTIC ZGN-EH10951T Fordhook (*HP 111) 1. Species Pepo Pepo 2. Kind/Use squash squash 3. Type summer (vegetable marrow) summer 4. Cotyledon length 42.8 mm 44.2 mm width 26.1 mm 30.3 mm apex rounded rounded veining plainly visible plainly visible color medium green medium green color (RHS Color Chart) 143A 143A 5. Seedling shape of cotyledons elliptic (Cora, Tivoli) circular intensity of green color of medium (Cora) medium cotyledons cross section of straight (Sunburst) concave cotyledons 6. Mature Plant growth habit bush bush plant type pilose pilose 7. Main Stem cross-section shape round round diameter at mid-point of 25.7 mm 26.3 mm 1^(st) internode average length 33.8 cm 35.2 cm average number of 23.3  25.7 internodes 8. Stem color completely green (Becky) completely green intensity of green color dark (Greyzini) dark mottling absent (Cinderella) absent tendrils absent to rudimentary absent to rudimentary (Goldrush, Sylvania) 9. Plant growth habit bush (Greyzini) bush branching absent (Goldi) absent bush varieties only: semi-erect (Arlesa) semi-erect attitude of petiole (excluding lower external leaves) 10. Leaves blade shape reniform reniform blade form deep lobed deep lobed margin dentate dentate margin edges frilled frilled average width 32.5 cm 30.2 cm average length 25.9 cm 25.4 cm leaf surface blistered blistered dorsal surface pubescence soft hairy bristled vental surface pubescence soft hairy bristled color medium green medium green color (RHS Color Chart) 137A 137A leaf blotching blotched with gray blotched with gray leaf blade: size medium (Ambassador) medium leaf blade: incisions deep (Civac) deep leaf blade: intensity of dark (Everest) light green color of upper surface leaf blade: silvery patches present (Civac) present leaf blade: relative area medium (Ambassador) very small covered by silvery patches average petiole length 31.9 cm 33.1 cm petiole length long (Autumn Gold, Baikal) long petiole: number of medium (Spidy) few prickles 11. Flower pistillate flower: average 11.5 cm 13.8 cm diameter pistillate flower: ovary drum-like drum-like pistillate flower: average 2.2 cm 2.2 cm pedicel length pistillate flower: margin curved curved shape pistillate flower: margin frilled frilled edges pistillate flower: average 1.3 mm 1.1 mm sepal width pistillate flower: average 4.5 mm 4.0 mm sepal length pistillate flower: color orange orange pistillate flower: color 17A 23A (RHS Color Chart) staminate flower: average 11.4 mm 16.1 mm sepal length staminate flower: average 2.0 mm 2.5 mm sepal width staminate flower: average 77.6 mm 128.0 mm pedicel length staminate flower: color orange orange staminate flower: RHS 23A 23A Color Chart Values female flower: ring at present (Aurore) present inner side of corolla female flower: color of green (Aurore, Early White green ring at inner side of Bush Scallop, President) corolla female flower: intensity of weak (Maya, Sardane) strong green color of ring at inner side of corolla (varieties with green ring at inner side of corolla) male flower: ring at inner present (Goldi) present side of corolla male flower: color of ring green (Austral, Belor, Goldi) green at inner side of corolla male flower: intensity of weak (Cara) medium green color of ring at inner side of corolla 12. Fruit market maturity: average 15.1 cm 17.6 cm length market maturity: average 2.5 cm 2.8 cm width stem end at market maturity: 1.1 cm 1.0 cm average width blossom end market maturity: average 155.5 gm 206.0 gm weight market maturity: shape banana banana according to variety type market maturity: apex rounded rounded market maturity: base rounded rounded market maturity: ribs inconspicuous inconspicuous market maturity: rib shallow shallow furrow depth market maturity: rib medium wide narrow furrow width market maturity: fruit smooth smooth surface market maturity: warts none none market maturity: blossom slightly extended raised acorn scar button young fruit: ratio length/ large (Carlotta) large maximum diameter (zucchini type varieties) young fruit: general shape cylindrical cylindrical (zucchini and rounded (Ambassador, Ibis) zucchini type varieties) young fruit: main color of green (Elite, Opal, Romano) green skin (excluding color of ribs or grooves) young fruit: intensity of very dark (Carnaval, dark green color of skin (only Corsair) varieties with green color of skin) general shape cylindrical cylindrical length (zucchini type medium (Cora) medium varieties) maximum diameter small (Goldi) small (zucchini type varieties) ratio length/maximum medium (Cora) medium diameter (zucchini type varieties) blossom end (zucchini and rounded pointed neck type varieties) grooves absent absent ribs absent absent main color of skin green (Ambassador, Baby green (excluding color of dots, Bear) patches, stripes and bands) intensity of green color of very dark (Baby Bear, very dark skin (only varieties with Sardane) green color of skin) stripes in grooves absent (Baby Bear, Jack Be absent Little) dots absent (Sunburst) absent secondary green color absent (Grey Zucchini, absent between ribs (excluding Small Sugar) dots) warts on skin absent absent size of flower scar small (Goldi) small length of peduncle short (Clarita) medium color of peduncle green (Ambassador) green intensity of green color of dark (Gold Rush) dark peduncle mottling of peduncle present (Elite) present ripe fruit: secondary color dark green dark green of skin (excluding color of mottles, patches, stripes and bands) secondary color of skin orange orange green hue absent (Jedida) absent ripe fruit: color of flesh yellow yellow (Sunburst, Vegetable Spaghetti) ripe fruit: lignified rind present (Elite, Little Gem, present Scallopini, Yellow Summer Crookneck) ripe fruit: structure of fibrous (Vegetable fibrous flesh Spaghetti) 13. Rind average thickness at 2.9 mm 2.3 mm medial toughness hard hard overall color pattern irregular irregular main or ground color greyish-green greyish-green main or ground color N189A N189A (RHS Color Chart) color of blotches grayish-orange grayish-orange RHS Color Chart for N163A N163D blotches color Rind: pattern of blotches not specific not specific 14. Flesh average blossom end 34.4 mm 34.0 mm thickness average medial thickness 35.8 mm 41.8 mm average stem end 31.0 mm 41.3 mm thickness texture (fine, granular, fine fine lumpy or stringy) texture (soft, firm or firm firm brittle) texture (dry, moist or moist moist juicy) flavor slightly sweet sweet quality good excellent color Yellowish-bronze yellow color (RHS Color Chart) 149D 4D 15. Seed Cavity average length 22.9 cm 36.0 cm average width 4.8 cm 7.5 cm location conforms to fruit shape conforms to fruit shape placental tissue moderately abundant moderately abundant center core inconspicuous inconspicuous 16. Fruit Stalks average length 3.2 cm 3.2 cm average diameter 2.7 cm 1.9 cm cross-section shape round irregular twisting not twisted not twisted tapering tapered not tapered straightness slightly curved straight texture spongy hard furrows deep deep surface spiny rough attachment end expanded slightly expanded detaches easily easily color dark green dark green color (RHS Color Chart) 143A 147A 17. Seeds average length 13.1 mm 14.0 mm average width 8.1 mm 9.0 mm average thickness 3.1 mm 2.7 mm face surface smooth smooth color cream cream color (RHS Color Chart) 160D 155C luster dull glossy margin curved straight margin edge rounded rounded separation from pulp moderately easy moderately easy average grams per 100 12.6 gm 14.3 gm seeds average number of seeds 84.9 121.5 per fruit seed coat normal normal size small (Delicata) medium shape broad elliptic (Baby Boo) elliptic hull present (Baby Bear, Elite) present appearance of hull fully developed (Elite) fully developed color of hull cream (De Nice à Fruit cream Rond) fruit type: zucchini fruit: patches, stripes or present (Elite, Greyzini) bands in ripe stage (if zucchini type) *These are typical values. Values may vary due to environment. Other values that are substantially equivalent are also within the scope of the invention.

C. Breeding Squash Plants

One aspect of the current invention concerns methods for producing seed of squash hybrid SV0474YG involving crossing squash lines ZGY-EH09012 and ZGN-EH10951T. Alternatively, in other embodiments of the invention, hybrid SV0474YG, line ZGY-EH09012, or ZGN-EH10951T may be crossed with itself or with any second plant. Such methods can be used for propagation of hybrid SV0474YG and/or the squash lines ZGY-EH09012 and ZGN-EH10951T, or can be used to produce plants that are derived from hybrid SV0474YG and/or the squash lines ZGY-EH09012 and ZGN-EH10951T. Plants derived from hybrid SV0474YG and/or the squash lines ZGY-EH09012 and ZGN-EH10951T may be used, in certain embodiments, for the development of new squash varieties.

The development of new varieties using one or more starting varieties is well known in the art. In accordance with the invention, novel varieties may be created by crossing hybrid SV0474YG followed by multiple generations of breeding according to such well known methods. New varieties may be created by crossing with any second plant. In selecting such a second plant to cross for the purpose of developing novel lines, it may be desired to choose those plants which either themselves exhibit one or more selected desirable characteristics or which exhibit the desired characteristic(s) when in hybrid combination. Once initial crosses have been made, inbreeding and selection take place to produce new varieties. For development of a uniform line, often five or more generations of selfing and selection are involved.

Uniform lines of new varieties may also be developed by way of double-haploids. This technique allows the creation of true breeding lines without the need for multiple generations of selfing and selection. In this manner true breeding lines can be produced in as little as one generation. Haploid embryos may be produced from microspores, pollen, anther cultures, or ovary cultures. The haploid embryos may then be doubled autonomously, or by chemical treatments (e.g. colchicine treatment). Alternatively, haploid embryos may be grown into haploid plants and treated to induce chromosome doubling. In either case, fertile homozygous plants are obtained. In accordance with the invention, any of such techniques may be used in connection with a plant of the invention and progeny thereof to achieve a homozygous line.

Backcrossing can also be used to improve an inbred plant. Backcrossing transfers a specific desirable trait from one inbred or non-inbred source to an inbred that lacks that trait. This can be accomplished, for example, by first crossing a superior inbred (A) (recurrent parent) to a donor inbred (non-recurrent parent), which carries the appropriate locus or loci for the trait in question. The progeny of this cross are then mated back to the superior recurrent parent (A) followed by selection in the resultant progeny for the desired trait to be transferred from the non-recurrent parent. After five or more backcross generations with selection for the desired trait, the progeny have the characteristic being transferred, but are like the superior parent for most or almost all other loci. The last backcross generation would be selfed to give pure breeding progeny for the trait being transferred.

The plants of the present invention are particularly well suited for the development of new lines based on the elite nature of the genetic background of the plants. In selecting a second plant to cross with SV0474YG and/or squash lines ZGY-EH09012 and ZGN-EH10951T for the purpose of developing novel squash lines, it will typically be preferred to choose those plants which either themselves exhibit one or more selected desirable characteristics or which exhibit the desired characteristic(s) when in hybrid combination. Examples of desirable traits may include, in specific embodiments, high seed yield, high seed germination, seedling vigor, high fruit yield, disease tolerance or resistance, and adaptability for soil and climate conditions. Consumer-driven traits, such as a fruit shape, color, texture, and taste are other examples of traits that may be incorporated into new lines of squash plants developed by this invention.

D. Performance Characteristics

As described above, hybrid SV0474YG exhibits desirable traits, as conferred by squash lines ZGY-EH09012 and ZGN-EH10951T. The performance characteristics of hybrid SV0474YG and squash lines ZGY-EH09012 and ZGN-EH10951T were the subject of an objective analysis of the performance traits relative to other varieties. The results of the analysis are presented below.

TABLE 4 Performance Data: Estimate of LSMEANS for Yield along with Mean Separation Grouping and 95% Confidence Interval LSMEANS 95% Confidence Interval ASRT3 MSGROUP for Yield Lower Upper LSMRANK LSD SV0474YG A 10.71 9.18 12.25 1 Pre-commercial hybrid 1 B 9.25 7.71 10.78 2 Pre-commercial hybrid 2 B 9.20 7.67 10.74 3 Pre-commercial hybrid 3 B 9.17 7.64 10.70 4 Pre-commercial hybrid 4 B 9.09 7.56 10.62 5 Pre-commercial hybrid 5 B 9.04 7.51 10.57 6 Pre-commercial hybrid 6 B 8.96 7.43 10.49 7 Pre-commercial hybrid 7 C 8.35 6.82 9.89 8 0.52 Market leader 1 D 7.83 6.30 9.36 9 Senator D 7.72 6.19 9.25 10 Competitor hybrid 1 D 7.66 6.12 9.19 11 Competitor hybrid 2 D 7.60 6.07 9.13 12 Competitor hybrid 3 DE 7.42 5.89 8.96 13 Pre-commercial hybrid 8 EF 7.08 5.55 8.61 14 Competitor hybrid 4 (dark) F 6.89 5.36 8.42 15 The analysis presented above represents the marketable yield per plant from a hybrid trial performed in SW Florida in late 2013 with 20 plants per plot, 20 replications, 20 harvest dates spanning 45 calendar days, with low viral and bacterial disease pressure and moderate fungal disease pressure. Units are in numbers of marketable fruits (subjective classification of fruit quality) by trained individuals.

E. Further Embodiments of the Invention

In certain aspects of the invention, plants described herein are provided modified to include at least a first desired heritable trait. Such plants may, in one embodiment, be developed by a plant breeding technique called backcrossing, wherein essentially all of the physiological and morphological characteristics of a variety are recovered in addition to a genetic locus transferred into the plant via the backcrossing technique. The term single locus converted plant as used herein refers to those squash plants which are developed by a plant breeding technique called backcrossing, wherein essentially all of the physiological and morphological characteristics of a variety are recovered in addition to the single locus transferred into the variety via the backcrossing technique. By essentially all of the physiological and morphological characteristics, it is meant that the characteristics of a plant are recovered that are otherwise present when compared in the same environment, other than an occasional variant trait that might arise during backcrossing or direct introduction of a transgene.

Backcrossing methods can be used with the present invention to improve or introduce a characteristic into the present variety. The parental squash plant which contributes the locus for the desired characteristic is termed the nonrecurrent or donor parent. This terminology refers to the fact that the nonrecurrent parent is used one time in the backcross protocol and therefore does not recur. The parental squash plant to which the locus or loci from the nonrecurrent parent are transferred is known as the recurrent parent as it is used for several rounds in the backcrossing protocol.

In a typical backcross protocol, the original variety of interest (recurrent parent) is crossed to a second variety (nonrecurrent parent) that carries the single locus of interest to be transferred. The resulting progeny from this cross are then crossed again to the recurrent parent and the process is repeated until a squash plant is obtained wherein essentially all of the physiological and morphological characteristics of the recurrent parent are recovered in the converted plant, in addition to the single transferred locus from the nonrecurrent parent.

The selection of a suitable recurrent parent is an important step for a successful backcrossing procedure. The goal of a backcross protocol is to alter or substitute a single trait or characteristic in the original variety. To accomplish this, a single locus of the recurrent variety is modified or substituted with the desired locus from the nonrecurrent parent, while retaining essentially all of the rest of the desired genetic, and therefore the desired physiological and morphological constitution of the original variety. The choice of the particular nonrecurrent parent will depend on the purpose of the backcross; one of the major purposes is to add some commercially desirable trait to the plant. The exact backcrossing protocol will depend on the characteristic or trait being altered and the genetic distance between the recurrent and nonrecurrent parents. Although backcrossing methods are simplified when the characteristic being transferred is a dominant allele, a recessive allele, or an additive allele (between recessive and dominant), may also be transferred. In this instance it may be necessary to introduce a test of the progeny to determine if the desired characteristic has been successfully transferred.

In one embodiment, progeny squash plants of a backcross in which a plant described herein is the recurrent parent comprise (i) the desired trait from the non-recurrent parent and (ii) all of the physiological and morphological characteristics of squash the recurrent parent as determined at the 5% significance level when grown in the same environmental conditions.

New varieties can also be developed from more than two parents. The technique, known as modified backcrossing, uses different recurrent parents during the backcrossing. Modified backcrossing may be used to replace the original recurrent parent with a variety having certain more desirable characteristics or multiple parents may be used to obtain different desirable characteristics from each.

With the development of molecular markers associated with particular traits, it is possible to add additional traits into an established germ line, such as represented here, with the end result being substantially the same base germplasm with the addition of a new trait or traits. Molecular breeding, as described in Moose and Mumm, 2008 (Plant Physiology, 147: 969-977), for example, and elsewhere, provides a mechanism for integrating single or multiple traits or QTL into an elite line. This molecular breeding-facilitated movement of a trait or traits into an elite line may encompass incorporation of a particular genomic fragment associated with a particular trait of interest into the elite line by the mechanism of identification of the integrated genomic fragment with the use of flanking or associated marker assays. In the embodiment represented here, one, two, three or four genomic loci, for example, may be integrated into an elite line via this methodology. When this elite line containing the additional loci is further crossed with another parental elite line to produce hybrid offspring, it is possible to then incorporate at least eight separate additional loci into the hybrid. These additional loci may confer, for example, such traits as a disease resistance or a fruit quality trait. In one embodiment, each locus may confer a separate trait. In another embodiment, loci may need to be homozygous and exist in each parent line to confer a trait in the hybrid. In yet another embodiment, multiple loci may be combined to confer a single robust phenotype of a desired trait.

Many single locus traits have been identified that are not regularly selected for in the development of a new inbred but that can be improved by backcrossing techniques. Single locus traits may or may not be transgenic; examples of these traits include, but are not limited to, herbicide resistance, resistance to bacterial, fungal, or viral disease, insect resistance, modified fatty acid or carbohydrate metabolism, and altered nutritional quality. These comprise genes generally inherited through the nucleus.

Direct selection may be applied where the single locus acts as a dominant trait. For this selection process, the progeny of the initial cross are assayed for viral resistance and/or the presence of the corresponding gene prior to the backcrossing. Selection eliminates any plants that do not have the desired gene and resistance trait, and only those plants that have the trait are used in the subsequent backcross. This process is then repeated for all additional backcross generations.

Selection of squash plants for breeding is not necessarily dependent on the phenotype of a plant and instead can be based on genetic investigations. For example, one can utilize a suitable genetic marker which is closely genetically linked to a trait of interest. One of these markers can be used to identify the presence or absence of a trait in the offspring of a particular cross, and can be used in selection of progeny for continued breeding. This technique is commonly referred to as marker assisted selection. Any other type of genetic marker or other assay which is able to identify the relative presence or absence of a trait of interest in a plant can also be useful for breeding purposes. Procedures for marker assisted selection are well known in the art. Such methods will be of particular utility in the case of recessive traits and variable phenotypes, or where conventional assays may be more expensive, time consuming or otherwise disadvantageous. Types of genetic markers which could be used in accordance with the invention include, but are not necessarily limited to, Simple Sequence Length Polymorphisms (SSLPs) (Williams et al., Nucleic Acids Res., 1 8:6531-6535, 1990), Randomly Amplified Polymorphic DNAs (RAPDs), DNA Amplification Fingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs), Arbitrary Primed Polymerase Chain Reaction (AP-PCR), Amplified Fragment Length Polymorphisms (AFLPs) (EP 534 858, specifically incorporated herein by reference in its entirety), and Single Nucleotide Polymorphisms (SNPs) (Wang et al., Science, 280:1077-1082, 1998).

F. Plants Derived by Genetic Engineering

Many useful traits that can be introduced by backcrossing, as well as directly into a plant, are those which are introduced by genetic transformation techniques. Genetic transformation may therefore be used to insert a selected transgene into a plant of the invention or may, alternatively, be used for the preparation of transgenes which can be introduced by backcrossing. Methods for the transformation of plants that are well known to those of skill in the art and applicable to many crop species include, but are not limited to, electroporation, microprojectile bombardment, Agrobacterium-mediated transformation and direct DNA uptake by protoplasts.

To effect transformation by electroporation, one may employ either friable tissues, such as a suspension culture of cells or embryogenic callus or alternatively one may transform immature embryos or other organized tissue directly. In this technique, one would partially degrade the cell walls of the chosen cells by exposing them to pectin-degrading enzymes (pectolyases) or mechanically wound tissues in a controlled manner.

An efficient method for delivering transforming DNA segments to plant cells is microprojectile bombardment. In this method, particles are coated with nucleic acids and delivered into cells by a propelling force. Exemplary particles include those comprised of tungsten, platinum, and preferably, gold. For the bombardment, cells in suspension are concentrated on filters or solid culture medium. Alternatively, immature embryos or other target cells may be arranged on solid culture medium. The cells to be bombarded are positioned at an appropriate distance below the macroprojectile stopping plate.

An illustrative embodiment of a method for delivering DNA into plant cells by acceleration is the Biolistics Particle Delivery System, which can be used to propel particles coated with DNA or cells through a screen, such as a stainless steel or Nytex screen, onto a surface covered with target cells. The screen disperses the particles so that they are not delivered to the recipient cells in large aggregates. Microprojectile bombardment techniques are widely applicable, and may be used to transform virtually any plant species.

Agrobacterium-mediated transfer is another widely applicable system for introducing gene loci into plant cells. An advantage of the technique is that DNA can be introduced into whole plant tissues, thereby bypassing the need for regeneration of an intact plant from a protoplast. Modern Agrobacterium transformation vectors are capable of replication in E. coli as well as Agrobacterium, allowing for convenient manipulations (Klee et al., Bio-Technology, 3(7):637-642, 1985). Moreover, recent technological advances in vectors for Agrobacterium-mediated gene transfer have improved the arrangement of genes and restriction sites in the vectors to facilitate the construction of vectors capable of expressing various polypeptide coding genes. The vectors described have convenient multi-linker regions flanked by a promoter and a polyadenylation site for direct expression of inserted polypeptide coding genes. Additionally, Agrobacterium containing both armed and disarmed Ti genes can be used for transformation.

In those plant strains where Agrobacterium-mediated transformation is efficient, it is the method of choice because of the facile and defined nature of the gene locus transfer. The use of Agrobacterium-mediated plant integrating vectors to introduce DNA into plant cells is well known in the art (Fraley et al., Bio/Technology, 3:629-635, 1985; U.S. Pat. No. 5,563,055).

Transformation of plant protoplasts also can be achieved using methods based on calcium phosphate precipitation, polyethylene glycol treatment, electroporation, and combinations of these treatments (see, e.g., Potrykus et al., Mol. Gen. Genet., 199:183-188, 1985; Omirulleh et al., Plant Mol. Biol., 21(3):415-428, 1993; Fromm et al., Nature, 312:791-793, 1986; Uchimiya et al., Mol. Gen. Genet., 204:204, 1986; Marcotte et al., Nature, 335:454, 1988). Transformation of plants and expression of foreign genetic elements is exemplified in Choi et al. (Plant Cell Rep., 13: 344-348, 1994), and Ellul et al. (Theor. Appl. Genet., 107:462-469, 2003).

A number of promoters have utility for plant gene expression for any gene of interest including but not limited to selectable markers, scoreable markers, genes for pest tolerance, disease resistance, nutritional enhancements and any other gene of agronomic interest. Examples of constitutive promoters useful for plant gene expression include, but are not limited to, the cauliflower mosaic virus (CaMV) P-35S promoter, which confers constitutive, high-level expression in most plant tissues (see, e.g., Odel et al., Nature, 313:810, 1985), including in monocots (see, e.g., Dekeyser et al., Plant Cell, 2:591, 1990; Terada and Shimamoto, Mol. Gen. Genet., 220:389, 1990); a tandemly duplicated version of the CaMV 35S promoter, the enhanced 35S promoter (P-e35S); 1 the nopaline synthase promoter (An et al., Plant Physiol., 88:547, 1988); the octopine synthase promoter (Fromm et al., Plant Cell, 1:977, 1989); and the figwort mosaic virus (P-FMV) promoter as described in U.S. Pat. No. 5,378,619 and an enhanced version of the FMV promoter (P-eFMV) where the promoter sequence of P-FMV is duplicated in tandem; the cauliflower mosaic virus 19S promoter; a sugarcane bacilliform virus promoter; a commelina yellow mottle virus promoter; and other plant DNA virus promoters known to express in plant cells.

A variety of plant gene promoters that are regulated in response to environmental, hormonal, chemical, and/or developmental signals can also be used for expression of an operably linked gene in plant cells, including promoters regulated by (1) heat (Callis et al., Plant Physiol., 88:965, 1988), (2) light (e.g., pea rbcS-3A promoter, Kuhlemeier et al., Plant Cell, 1:471, 1989; maize rbcS promoter, Schaffner and Sheen, Plant Cell, 3:997, 1991; or chlorophyll a/b-binding protein promoter, Simpson et al., EMBO J., 4:2723, 1985), (3) hormones, such as abscisic acid (Marcotte et al., Plant Cell, 1:969, 1989), (4) wounding (e.g., wunl, Siebertz et al., Plant Cell, 1:961, 1989); or (5) chemicals such as methyl jasmonate, salicylic acid, or Safener. It may also be advantageous to employ organ-specific promoters (e.g., Roshal et al., EMBO J., 6:1155, 1987; Schernthaner et al., EMBO J., 7:1249, 1988; Bustos et al., Plant Cell, 1:839, 1989).

Exemplary nucleic acids which may be introduced to plants of this invention include, for example, DNA sequences or genes from another species, or even genes or sequences which originate with or are present in the same species, but are incorporated into recipient cells by genetic engineering methods rather than classical reproduction or breeding techniques. However, the term “exogenous” is also intended to refer to genes that are not normally present in the cell being transformed, or perhaps simply not present in the form, structure, etc., as found in the transforming DNA segment or gene, or genes which are normally present and that one desires to express in a manner that differs from the natural expression pattern, e.g., to over-express. Thus, the term “exogenous” gene or DNA is intended to refer to any gene or DNA segment that is introduced into a recipient cell, regardless of whether a similar gene may already be present in such a cell. The type of DNA included in the exogenous DNA can include DNA which is already present in the plant cell, DNA from another plant, DNA from a different organism, or a DNA generated externally, such as a DNA sequence containing an antisense message of a gene, or a DNA sequence encoding a synthetic or modified version of a gene.

Many hundreds if not thousands of different genes are known and could potentially be introduced into a squash plant according to the invention. Non-limiting examples of particular genes and corresponding phenotypes one may choose to introduce into a squash plant include one or more genes for insect tolerance, such as a Bacillus thuringiensis (B.t.) gene, pest tolerance such as genes for fungal disease control, herbicide tolerance such as genes conferring glyphosate tolerance, and genes for quality improvements such as yield, nutritional enhancements, environmental or stress tolerances, or any desirable changes in plant physiology, growth, development, morphology or plant product(s). For example, structural genes would include any gene that confers insect tolerance including but not limited to a Bacillus insect control protein gene as described in WO 99/31248, herein incorporated by reference in its entirety, U.S. Pat. No. 5,689,052, herein incorporated by reference in its entirety, U.S. Pat. Nos. 5,500,365 and 5,880,275, herein incorporated by reference in their entirety. In another embodiment, the structural gene can confer tolerance to the herbicide glyphosate as conferred by genes including, but not limited to Agrobacterium strain CP4 glyphosate resistant EPSPS gene (aroA:CP4) as described in U.S. Pat. No. 5,633,435, herein incorporated by reference in its entirety, or glyphosate oxidoreductase gene (GOX) as described in U.S. Pat. No. 5,463,175, herein incorporated by reference in its entirety.

Alternatively, the DNA coding sequences can affect these phenotypes by encoding a non-translatable RNA molecule that causes the targeted inhibition of expression of an endogenous gene, for example via antisense- or cosuppression-mediated mechanisms (see, for example, Bird et al., Biotech. Gen. Engin. Rev., 9:207, 1991). The RNA could also be a catalytic RNA molecule (i.e., a ribozyme) engineered to cleave a desired endogenous mRNA product (see for example, Gibson and Shillito, Mol. Biotech., 7:125, 1997). Thus, any gene which produces a protein or mRNA which expresses a phenotype or morphology change of interest is useful for the practice of the present invention.

G. Definitions

In the description and tables herein, a number of terms are used. In order to provide a clear and consistent understanding of the specification and claims, the following definitions are provided:

Allele: Any of one or more alternative forms of a gene locus, all of which alleles relate to one trait or characteristic. In a diploid cell or organism, the two alleles of a given gene occupy corresponding loci on a pair of homologous chromosomes.

Backcrossing: A process in which a breeder repeatedly crosses hybrid progeny, for example a first generation hybrid (F₁), back to one of the parents of the hybrid progeny. Backcrossing can be used to introduce one or more single locus conversions from one genetic background into another.

Crossing: The mating of two parent plants.

Cross-pollination: Fertilization by the union of two gametes from different plants.

Diploid: A cell or organism having two sets of chromosomes.

Emasculate: The removal of plant male sex organs or the inactivation of the organs with a cytoplasmic or nuclear genetic factor or a chemical agent conferring male sterility.

Enzymes: Molecules which can act as catalysts in biological reactions.

F₁ Hybrid: The first generation progeny of the cross of two nonisogenic plants.

Genotype: The genetic constitution of a cell or organism.

Haploid: A cell or organism having one set of the two sets of chromosomes in a diploid.

Linkage: A phenomenon wherein alleles on the same chromosome tend to segregate together more often than expected by chance if their transmission was independent.

Marker: A readily detectable phenotype, preferably inherited in codominant fashion (both alleles at a locus in a diploid heterozygote are readily detectable), with no environmental variance component, i.e., heritability of 1.

Phenotype: The detectable characteristics of a cell or organism, which characteristics are the manifestation of gene expression.

Quantitative Trait Loci (QTL): Quantitative trait loci (QTL) refer to genetic loci that control to some degree numerically representable traits that are usually continuously distributed.

Resistance: As used herein, the terms “resistance” and “tolerance” are used interchangeably to describe plants that show no symptoms to a specified biotic pest, pathogen, abiotic influence or environmental condition. These terms are also used to describe plants showing some symptoms but that are still able to produce marketable product with an acceptable yield. Some plants that are referred to as resistant or tolerant are only so in the sense that they may still produce a crop, even though the plants are stunted and the yield is reduced.

Regeneration: The development of a plant from tissue culture.

Royal Horticultural Society (RHS) color chart value: The RHS color chart is a standardized reference which allows accurate identification of any color. A color's designation on the chart describes its hue, brightness and saturation. A color is precisely named by the RHS color chart by identifying the group name, sheet number and letter, e.g., Yellow-Orange Group 19A or Red Group 41B.

Self-pollination: The transfer of pollen from the anther to the stigma of the same plant.

Single Locus Converted (Conversion) Plant: Plants which are developed by a plant breeding technique called backcrossing, wherein essentially all of the physiological and morphological characteristics of a squash variety are recovered in addition to the characteristics of the single locus transferred into the variety via the backcrossing technique and/or by genetic transformation.

Substantially Equivalent: A characteristic that, when compared, does not show a statistically significant difference (e.g., p=0.05) from the mean.

Tissue Culture: A composition comprising isolated cells of the same or a different type or a collection of such cells organized into parts of a plant.

Transgene: A genetic locus comprising a sequence which has been introduced into the genome of a squash plant by transformation.

H. Deposit Information

A deposit of squash hybrid SV0474YG and the inbred squash lines ZGY-EH09012 and ZGN-EH10951T, disclosed above and recited in the claims, has been made with the American Type Culture Collection (ATCC), 10801 University Blvd., Manassas, Va. 20110-2209. The dates of deposit was May 23, 2014. The accession numbers for those deposited seeds of squash hybrid SV0474YG and the inbred squash lines ZGY-EH09012 and ZGN-EH10951T are ATCC Accession No. PTA-121307, ATCC Accession No. PTA-121313 and ATCC Accession No. PTA-121308, respectively. Upon issuance of a patent, all restrictions upon the deposits will be removed, and the deposits are intended to meet all of the requirements of 37 C.F.R. §1.801-1.809. The deposits will be maintained in the depository for a period of 30 years, or 5 years after the last request, or for the effective life of the patent, whichever is longer, and will be replaced if necessary during that period.

Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity and understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the invention, as limited only by the scope of the appended claims.

All references cited herein are hereby expressly incorporated herein by reference. 

What is claimed is:
 1. A squash plant comprising at least a first set of the chromosomes of squash line ZGY-EH09012 or squash line ZGN-EH10951T, a sample of seed of said lines having been deposited under ATCC Accession Number PTA-121313 and ATCC Accession Number PTA-121308, respectively.
 2. A squash seed comprising at least a first set of the chromosomes of squash line ZGY-EH09012 or squash line ZGN-EH10951T, a sample of seed of said lines having been deposited under ATCC Accession Number PTA-121313 and ATCC Accession Number PTA-121308, respectively.
 3. The plant of claim 1, which is an inbred.
 4. The plant of claim 1, which is a hybrid.
 5. The seed of claim 2, which is an inbred.
 6. The seed of claim 2, which is a hybrid.
 7. The plant of claim 4, wherein the hybrid plant is squash hybrid SV0474YG, a sample of seed of said hybrid SV0474YG having been deposited under ATCC Accession Number PTA-121307.
 8. The seed of claim 6, defined as a seed of squash hybrid SV0474YG, a sample of seed of said hybrid SV0474YG having been deposited under ATCC Accession Number PTA-121307.
 9. The seed of claim 2, defined as a seed of line ZGY-EH09012 or line ZGN-EH10951T.
 10. A plant part of the plant of claim
 1. 11. The plant part of claim 10, further defined as a leaf, an ovule, pollen, a fruit, or a cell.
 12. A squash plant having all the physiological and morphological characteristics of the squash plant of claim
 7. 13. A tissue culture of regenerable cells of the plant of claim
 1. 14. The tissue culture according to claim 13, comprising cells or protoplasts from a plant part selected from the group consisting of embryos, meristems, cotyledons, pollen, leaves, anthers, roots, root tips, pistil, flower, seed and stalks.
 15. A squash plant regenerated from the tissue culture of claim
 13. 16. A method of vegetatively propagating the squash plant of claim 1 comprising the steps of: (a) collecting tissue capable of being propagated from the plant according to claim 1; (b) cultivating said tissue to obtain proliferated shoots; and (c) rooting said proliferated shoots to obtain rooted plantlets.
 17. The method of claim 16, further comprising growing at least a first squash plant from said rooted plantlets.
 18. A method of introducing a desired trait into a squash line comprising: (a) utilizing as a recurrent parent a plant of either squash line ZGY-EH09012 or squash line ZGN-EH10951T, by crossing a plant of squash line ZGY-EH09012 or squash line ZGN-EH10951T with a second donor squash plant that comprises a desired trait to produce F1 progeny, a sample of seed of said lines having been deposited under ATCC Accession Number PTA-121313, and ATCC Accession Number PTA-121308, respectively; (b) selecting an F1 progeny that comprises the desired trait; (c) backcrossing the selected F1 progeny with a plant of the same squash line used as the recurrent parent in step (a), to produce backcross progeny; (d) selecting backcross progeny comprising the desired trait and the physiological and morphological characteristics of the recurrent parent squash line used in step (a); and (e) repeating steps (c) and (d) three or more times to produce selected fourth or higher backcross progeny that comprise the desired trait, and otherwise comprise essentially all of the physiological and morphological characteristics of the recurrent parent squash line used in step (a).
 19. A squash plant produced by the method of claim
 18. 20. A method of producing a squash plant comprising an added trait, the method comprising introducing a transgene conferring the trait into a plant of squash hybrid SV0474YG, squash line ZGY-EH09012 or squash line ZGN-EH10951T, a sample of seed of said hybrid and lines having been deposited under ATCC Accession Number PTA-121307, ATCC Accession Number PTA-121313, and ATCC Accession Number PTA-121308, respectively.
 21. A squash plant produced by the method of claim
 20. 22. The plant of claim 1, further comprising a transgene.
 23. The plant of claim 22, wherein the transgene confers a trait selected from the group consisting of male sterility, herbicide tolerance, insect resistance, pest resistance, disease resistance, modified fatty acid metabolism, environmental stress tolerance, modified carbohydrate metabolism and modified protein metabolism.
 24. The plant of claim 1, further comprising a single locus conversion.
 25. The plant of claim 24, wherein the single locus conversion confers a trait selected from the group consisting of male sterility, herbicide tolerance, insect resistance, pest resistance, disease resistance, modified fatty acid metabolism, environmental stress tolerance, modified carbohydrate metabolism and modified protein metabolism.
 26. A method for producing a seed of a squash plant derived from at least one of squash hybrid SV0474YG, squash line ZGY-EH09012 or squash line ZGN-EH10951T comprising the steps of: (a) crossing a squash plant of hybrid SV0474YG, line ZGY-EH09012 or line ZGN-EH10951T with itself or a second squash plant; a sample of seed of said hybrid and lines having been deposited under ATCC Accession Number PTA-121307, ATCC Accession Number PTA-121313, and ATCC Accession Number PTA-121308, respectively; and (b) allowing seed of a hybrid SV0474YG, line ZGY-EH09012 or line ZGN-EH10951T-derived squash plant to form.
 27. The method of claim 26, further comprising the steps of: (c) selfing a plant grown from said hybrid SV0474YG, line ZGY-EH09012 or line ZGN-EH10951T-derived squash seed to yield additional hybrid SV0474YG, line ZGY-EH09012 or line ZGN-EH10951T-derived squash seed; (d) growing said additional hybrid SV0474YG, line ZGY-EH09012 or line ZGN-EH10951T-derived squash seed of step (c) to yield additional hybrid SV0474YG, line ZGY-EH09012 or line ZGN-EH10951T-derived squash plants; and (e) repeating the crossing and growing steps of (c) and (d) to generate at least a first further hybrid SV0474YG, line ZGY-EH09012 or line ZGN-EH10951T-derived squash plant.
 28. The method of claim 26, wherein the second squash plant is of an inbred squash line.
 29. The method of claim 26, comprising crossing line ZGY-EH09012 with line ZGN-EH10951T, a sample of seed of said lines having been deposited under ATCC Accession Number PTA-121313, and ATCC Accession Number PTA-121308, respectively.
 30. The method of claim 27, further comprising: (f) crossing the further hybrid SV0474YG, line ZGY-EH09012 or line ZGN-EH10951T-derived squash plant with a second squash plant to produce seed of a hybrid progeny plant.
 31. A plant part of the plant of claim
 7. 32. The plant part of claim 31, further defined as a leaf, a flower, a fruit, an ovule, pollen, or a cell.
 33. A method of producing a squash seed comprising crossing the plant of claim 1 with itself or a second squash plant and allowing seed to form.
 34. A method of producing a squash fruit comprising: (a) obtaining the plant according to claim 1, wherein the plant has been cultivated to maturity; and (b) collecting a squash from the plant. 